What's Wrong With “more better”?

Nothing! As long as you don’t understand grammar. If you did, you’d quickly realize that better is a comparative adverb (good, better, best) and more is an adjective. Which makes “more better” a reverse of modifier guidelines.

Listen closely, I’ll say this only once…more:

Adjectives modify Nouns and Pronouns — period.

Adverbs, on the other hand, modify Verbs, other Adverbs,
AND Adjectives.

Stick with me, sweetheart, and you’ll get this stuff down soon!